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John Cuthber

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Everything posted by John Cuthber

  1. Err, I think "Pi in base Pi is 10. " is misleading. Non- integer bases run into problems. In base 10 I can use all the digits 0 to 9; there's no need for anything bigger than 9. In binary I only have 1 and 0. What digits can I use in base 0.5 ? And, at the risk of arguing against myself, pi is random in a rather obscure sense. Given that a particular digit is, for example, 3 does not give any indication of what the next digit is. Similarly the sequence of digits 25356 is just as likely to be followed by any digit as any other. It is, in fact, used in random number generation and, as such, it was tested for randomness (of this type) a long time ago to a lot of digits. It passed so there's not going to be anything interesting in the first couple of hundred digits. http://news.uns.purdue.edu/html4ever/2005/050426.Fischbach.pi.html
  2. You should look into following your doctor's advice.
  3. Pi can be calculated, if you tell me what digit you want, I can (in principle) tell you what it is. It's not random. The 3rd digit of pi (in denary) is always going to be 4. Nothing random about it and the same goes for any other digit in any base. You cannot have a changing value of the radius of the universe if it is calculated from a collection of constants (Planck's constant and some parameter calculated from the (randomness of the) digits of pi). Whenever you calculate it it will give the same answer. 6 times 7 will still be 42 in 13.7 billion years and it was just the same as close back to the big bang as you like. Whather or not pi was still about 3 before the big bang is a matter of philosphy and I'm not sure the question has a meaning. If you take the view that maths was discovered (ie like America, it was already there for Columbus (or whoever) to find) then pi was 3 and a bit before anyone anyone noticed it and it will still be 3 and a bit forever. Since as you say, the radius is changing, there is a problem with your theory.
  4. "yeah, thats right eg. cis-2-chloroethene or trans-2-chloroethene" Err, that's a rather poor example. In one case the chlorine is cis to a hydrogen and trans to the other one. In the other case the Cl is trans to a hydrogen and cis to the other. There's only one isomer. For what it's worth that compound is 1 chloroethene rather than 2chloroethene Anyway, the answer seems to depend who you ask but, for example, names like "cis,cis,cis,trans-[]-fenestrane" can be found on the 'net. Here are the "official" rules from people who can't spell sulphur http://www.acdlabs.com/iupac/nomenclature/
  5. I'm puzzled, why don't you think the reaction has gone to completion? Since adding more eggshells doesn't produce more CO2 I think the acid has been used up. Btw, please give me the names of insoluble acetates that could plausible be present.
  6. "I'm not sure if it's the same GABA I looked up on the internet that comes in pills and powder form like some sort of supplement (vitamin packaging and whatnot). " No. It's a different chemical altogether. http://en.wikipedia.org/wiki/Gabapentin rather than http://en.wikipedia.org/wiki/GABA
  7. "However, there is a lot more CO2 in the atmosphere than methane, so it would not be very useful to curb methane emmisions for the sole purpose of stopping global warming." Erm? Isn't that a good reason for limiting release of methane (and the CFCs too). There's lots of CO2 in the air. IR at any wavelength where CO2 absorb meets lots of CO2, so little gets through. A bit more CO2 doesn't matter so much because it is already absorbing all the IR that it could absorb. Methane is much less common so the absorbtion of the sun's IR isn't so nearly complete. More methane means more absorbtion.
  8. "I would like to know more about how can we solve the climate change and if cow more responsible than us to the release of CO2" We could stop farming cows but, since cows (and sheep etc) can eat grass which we cannot eat, there might be a problem feeding the world. Also, I like beef and I don't own a car so I'd obviously rather give up cars than cattle.
  9. All this reminds me of a dilbert cartoon http://weblogs.asp.net/mhawley/archive/2004/10/25/247203.aspx
  10. "I need the exact solutions to some calculations and not an estimate to the solution such as X^99 or an approximation of Pi or e." Good luck with the exact value of those transcendental numbers.
  11. How do you propose to measure the radius of the universe? Last time I heard most people thought it was infinite. If there's an "edge" wouldn't dividing that radius by c give at least as good an estimate? Whenever you do the maths the value for "The proposed value would be such that the precision at which the change in randomness occurs " will be the same because one of the nice things about maths is that it is constant. Planck's constant is also a constant. The radius of the universe is either expanding or infinite. If it's infinite the expression you give makes no sense. If it is expanding then you are saying that something constant is a function of something that is changing.
  12. Reduction of WO3 by hydrogen at high temp is the industrial process I think. It's not very cheap.
  13. I'm not saying that the stuff is hugely toxic. I just think it's plain dumb to make a statement like "No, it's not toxic" when, in fact, it is toxic. This is meant to be a scientific forum. Plainly inaccurate postings like that serve no purpose, worse they may persuade some fool to ignore the toxic nature of Mn compounds and harm themselves. You may wish to disregard those people as candidates for a Darwin award, but that's not a point I'd like to have to argue with their family or their lawyer. As for this comment "john, that refers to manganese metal, not its dioxide." What are you talking about? Do you really believe that Mn wouldn't get oxidised in the body? Do you really think that MnO2 wouldn't get reduced? Don't you understand that the toxicity refered to in the Wiki article is about welding fumes? Do you think those fumes are the metal rather than its oxide(s)? If anything the higher oxidation states are likely to do more damage. The comment "MnO2 isn`t going to cause ANY harm :)" is simply at odds with the facts; Mn has caused harm and it probably will again.
  14. For a start, cars emit carbon monoxide (CO) in quite large amounts whereas cows scarcely produce any. If you are talking about CO2 then you have to think about another aspect of it. Cows (an people too) produce a fair amount of CO2. On the other hand, all the CO2 a cow produced was CO2 in the atmosphere recently. Then it was turned into grass by photosynthesis and some of it was subsequently released, in the long run, all that CO2 will end up back in the atmosphere. The car on the other hand is producing CO2 that was locked away from the atmosphere millions of years ago.
  15. "No, it's not toxic." Want to bet on that? http://en.wikipedia.org/wiki/Manganism
  16. "Quote: Originally Posted by John Cuthber Dogs spend enough time humping their owners' legs to prove that they certainly don't know they are dogs, I question whether they have a sense of self. If a dog doesn't have an understanding that it is an individual then how can it think "I am in pain"- there isn't an "I" to think that. Only just caught up with this thread, But this "example" made me laugh like a drain. Just substitute man and plastic blow-up dolls for dogs and legs, or even for students' rolled up socks, and we are asked to conclude that if a man does such things he likewise has no notion of pain or self. Doll and sock shaggers are thus a legitimate part of the Vegan food chain. Canibalism rules, O.K.? Way to go, Vegans!" Yeah, sure, if that were the only eidence about dogs- which it isn't.
  17. Err? "the eyeball itself is incapable of feeling pain," Having scratched the cornea of my eye a few years back I can tell you the eye is quite definitely capable of feeling pain. It left me lying in bed for a day because I couldn't see. Even with the damaged eye shut , every time I looked round at something it seemed to scrape the damaged bit across the inside of the eyelid (which, lets face it is pretty smooth really). Did you know that when you listen to stereo musc recordings your eyes tend to follow the loudest sound? I didn't until every movement of the eye hurt like blazes. BTW, Ecoli, if you haven't gone to the local hospital's emergency room yet, might I ask what you are waiting for?
  18. "its difficult to decide what an animals brain can do when its completely different from ours. maybe they are communicating on a very high level and we cant tell because they are doing it with a part of their brain that we dont have. they could be more intelligent than we realize since we dont understand how they work." Not really, we can still see if they can count or recognise themself in a mirror or remember where their food was. It doesn't matter how the brain is made.
  19. "One thing that does concern me, though, is octopi; they're clearly capable of advanced learning and problem solving, but their brain is massively different from ours. How would one even make a meaningful comparison between the two?" Well, if they can tell me that then I accept I shouldn't eat them. Actually, I didn't think much of squid when I tried it (a bit like eating rubber bands) so I won't bother with octopus. Seriously, does it matter what their brains are like. It's what they can do with them that matters.
  20. Tater, a quick hint for you, where exactly did you imagine the chlorine atom in the middle of a perchlorate would come from if you electrolysed NaNO3 and KNO4 (whatever the hell that is)? BTW while I'm quite happy to spell, for example, oxidise with a z ie oxidize, I get upset about "electrolyze" and "hydrolyze". It's not "just a matter of opinion". It's plain wrong. The words are derived from lysis meaning to split. To make an oxide is to oxidi(s/z)e. "Electrolyze" only makes sense if you think you are making an "electrol".
  21. OK, fair enough, what's your idea and we will see if we can confirm it.
  22. Just in case anyone takes any of the post above seriously, nickel carbonyl is really rather bad for you.
  23. I'm paranoid enough that I'd include an anti suck back trap. Not least because I suspect this is a homework question. I have neutralised 50% NaOH solution with conc sulphuric but I wouldn't want to do it by accident (and I don't really reccomend it).
  24. "Chimps certainly do have a sense of self; I can't see anyone saying there's room in a cockroach brain for that sort of abstract thinking. Looked at politicians lately?" JohnB I sympathise with you for having to put up with the opportunity to chose which bunch of liars get in next time, but that's no reason to insult the chimps and cockroaches. (BTW, the set with no members is, I understand, very important in mathematics. I think the fact that all null sets are the same means there's only one "empty set" and mathematicians then use that as the definition of "1"; the rest of us know what "1" is; it's half of "2")
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